User's Manual

Chapter 9 Network Address Translation (NAT)
P-2612HW Series User’s Guide
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9.5.4 NAT Application
The following figure illustrates a possible NAT application, where three inside LANs
(logical LANs using IP alias) behind the ZyXEL Device can communicate with three
distinct WAN networks.
Figure 118 NAT Application With IP Alias
9.5.5 NAT Mapping Types
NAT supports five types of IP/port mapping. They are:
• One to One: In One-to-One mode, the ZyXEL Device maps one local IP address
to one global IP address.
• Many to One: In Many-to-One mode, the ZyXEL Device maps multiple local IP
addresses to one global IP address. This is equivalent to SUA (for instance, PAT,
port address translation), ZyXEL’s Single User Account feature that previous
ZyXEL routers supported (the SUA Only option in today’s routers).
Internet
Corporation B
NAT Server
192.168.3.1
LAN3: 192.168.3.X
Network Server
“R&D”=192.168.3.1
WAN Addresses: LAN Addresses: (Default IPs)
IGA 1 ---------------> 192.168.1.1
IGA 2 ---------------> 192.168.2.1
IGA 3 ---------------> 192.168.3.1
NAT Server
192.168.2.1
LAN2: 192.168.2.X
Network Server
“Sales”=192.168.2.1
Server in
R&D Network
=IP3 (IGA 3)
NAT Server
192.168.1.1
LAN2: 192.168.1.X
Network Server
“Admin=192.168.1.1
Corporation A
Server in
Sales Network
=IP2 (IGA 2)
Server in
Admin Network
=IP1 (IGA 1)